It wasn’t until Beethoven’s twenties that he began to lose his hearing in any significant way, and by that time he had already studied with the likes of Joseph Haydn and Mozart.
He gave his first solo concert in his late twenties. However, by the time he reached his early thirties his hearing was gone, and he could no longer properly play the piano.
At this point, he admitted to considering suicide because his personal loss was so overwhelming. To the benefit of classical music, he discovered he could, despite being deaf, still compose.
He wrote symphonies and concertos for the remainder of his life, most of them being the best he’d ever written.
Beethoven’s overall accomplishments included writing scores of written music, extending the length of the piano concerto and symphony, and adding instruments to the orchestra, including the piccolo and the trombone.
And what would an orchestra be without a trombone?